There is broad recognition of the threat posed by heat (IR energy) seeking missiles to both military and commercial aviation. In the mid 1970's, defensive systems were rapidly developed and deployed to increase military aircraft battlefield survivability. These systems were highly successful in countering IR-missile threats and have proven themselves invaluable to both military and commercial sectors. These older prior art systems are based on a multi-spectral sources filtered to provide desired IR-missile jam wavelengths. The source must provide significant modulated energy emission, to provide appropriate jamming effectiveness. A major benefit of many older systems is that they are always “ON” and continually providing “staring” protection. The source emission can be tailored to the signature of the platform being protected or provide radiated fields of protection dictated by the geometry of the emitter. The “staring” characteristic ordinarily provides “JAM in the TUBE” protection. That is, missiles affected by such prior art staring systems typically can not launch since the missile's guidance system can not ‘lock’ onto the desired target.
A drawback to some such prior art systems is that they may be specifically designed for protection against what is referred to as Band I IR missile threats. IR missile technology has evolved to include improved jamming rejection and changes in spectral sensitivity (wavelength); this necessitates new methods to oppose the new threats. These newer IR-missiles are referred to as Band IV threats. To address the advanced technology, infrared countermeasures (IRCM) have followed with increasingly complex and sophisticated protection solutions that basically discards the older technologies. Today's advanced IRCM includes integrated missile warning and precision guided laser jamming technology. The latest Directional Infrared Countermeasure (DIRCM) systems direct high intensity modulated IR lasers on the incoming missile's dome, thus jamming the guidance control system. DIRCM systems differ from Staring systems in that they are significantly more complicated than the older staring systems. In addition, DIRCM systems must be cued by an advanced missile warning system prior to attempting to point and jam with sufficient precision and apply Energy on Target (EoT) to defeat the threat in a moving and turbulent environment. These complexities and the addition of many interrelated subsystems (i.e. Missile Warning, Gimbal, Tracking Camera, Cryogenic Coolers, and Lasers etc.) inherently increase life cycle cost and reduce system reliability. Consequently, the bulk of our military force's aircraft fleet is unprotected against advanced IR missiles. Many aircraft in our current military aircraft fleets, however, are still protected with such older staring IRCM systems.
A need, therefore, exists for still better and economic ways to protect aircraft from the more advanced IR guided missile threats being developed.